Prime Focus

The newsletter of the Tri-Valley Stargazers November 1997.
Translated (roughly) from postscript into HTML for your browsing and downloading pleasure.
The Cartwheel Galaxy, some 500 million light-years away, can be found in the constellation Sculptor. It has apparently collided with a smaller intruder galaxy, perhaps one of the two to the right. Star formation is occurring in the outer ring resulting from the collision. Supernovae are forming in both the ring and an arc extending beyond it. (Credit: Kirk Borne (STScI) and NASA)


Club news notes
What's Up in November
Comet Comments
Color Astrophotography
Stellar Seller
Stanford SOLAR Center

TVS presents

What: Image processing with Photoshop
When: November 21, 1997 Conversation 7:00 PM, Business Meeting 7:30 PM
Who: Chuck Vaughn
Where: Unitarian Universalist Church in Livermore, 1893 N. Vasco Rd.

Make your plans now to attend the November general meeting. The last time club member Chuck Vaughn demonstrated his skills in astrophotography, we had a standing room-only crowd.

Chuck plans a demonstration of image processing on astrophotos, using Adobe Photoshop. Many of the capabilities of Photoshop parallel work that can be done in the traditional darkroom, but are much easier to achieve. Additionally, Photoshop offers many functions that cannot be performed in the darkroom.

The demonstration will begin when Chuck scans negatives into Photoshop. He will use a Polaroid slide scanner and show how to optimize a scan to create the best image for Photoshop to process. He will bring both black and white and color negatives.

Digital darkroom tricks that Chuck will show us from Photoshop include: contrast stretching, color balancing, and color negative stacking - a technique few could accomplish without access to a professional darkroom.

Club News Notes

Star hopping down under

Editor's note: Bob Braddy, vice-president of TVS until his transfer to London, now finds him self looking up from Perth, Australia. He sends this note so that we can share his astronomical adventures in the Southern Hemisphere.

Further update. I borrowed a car and drove about 30 kilometres north of Perth where I was able to see both the SMC and LMC. The Milky Way was just visible and I could see the two galaxies with averted vision. The skys weren't Sky Shack quality; closer to what we get at our star parties at the park in Livermore. I had clouds on the horizon over Perth which added some light.

The SMC and LMC look like fuzzy parts of the Milky Way that broke off and drifted away from the main stream. In my 12X50's the LMC showed some elongation, almost rectangular, and I could resolve no stars at 12X. The SMC was even less interesting. The Milky Way I could see was the part that goes from Sagittarius through Centarus on south, which South of Centarus did not appear too interesting.

Centarus is a nice constellation and would be one of our major constellations if it had been higher in the Northern Sky. Musca (the fly I think) is not a bad little group of stars despite its name. I could not see the Eta Carina region or Hale-Bopp (yes it's still here at mag 6) due to clouds off to the SE. All in all, it would not take much to see everything down here that you can't see there with a medium (8") scope in a few clear all night sessions. The sky is largely empty of bright constellations to the South so I guess you might have a large collection of faint fuzzies accessiblein a large (16" or more scope).

I stopped into a telescope store in downtown Perth with some serious scopes (14" Celestron SC for example). Looks like they would organize an observing expedition for a price with scopes. So if anyone gets sent down here on businesss, that could be an option if you had a few days. Just make sure it's their summer. They say it rains every night in their winter.

The bookstores in Perth are incredible. There are about 20 within three blocks of my hotel and about half are quality used book stores and many are "technical" book stores. Something to do on those rainy nights in winter.

Regards, Bob

Time to renew

The winter solstice hits next month, and that means TVS dues are payable any time over the next few months. the membership/renewal application bears the good news that dues have not increased this year.

Subscriptions to Sky & Telescope and Astronomy are again available at discounted club subscription rates. S&T has jumped its rate slightly, to $27 per year; Astronomy remains at $24 annually. Magazine subscriptions (or renewals) are mailed the day after the February general meeting, so they are slightly offset from the January to December TVS membership year.

Renewals and subscriptions may be mailed to our post office box (see below), or you may bring a completed form and check to any general meeting between now and February.

The more things change...

Once again, new moon weekends and TVS general meetings approach conjunction. To keep these dark weekends free of club conflicts, we will shift the general meeting night to the second Friday of each month, beginning in January 1998.

When planning your calendar for next year, please reserve the following dates for general meetings.

January 9
February 13
March 13
April 10
May 8
June 12
July 10
August 14
September 11
October 9
November 13
December 11

Library acquisitions

Club librarian Chris Cody has tabulated results from the library questionnaire. Observing aids were the most mentioned request for new purchases. To meet that need, the club will purchase five copies of the 1998 Royal Astronomical Handbook, a laminated edition of the Sky Atlas 2000, and five copies of the Bright Star Atlas.

Other helpful observing tools will include books like Touring the Universe Through Binoculars and Robert Garfinkle's Starhopping.

Some of the club's library materials are a bit tardy and downright overdue. If you hold one of these late books, periodicals, cassettes, or video tapes, return it at the November general meeting or call Chris at (707) 747-6550 and tell him when to expect it.

Star parties

We expect to receive requests from teachers for star parties, and Rich Green, school star party chair, is in need of help. He has created an e-mail list of members interested in assisting at star parties, but needs help organizing this group.

If you are interested in taking the lead on school star parties, contact Rich Green at (510) 449-2190 or call club president Dave Anderson at (510) 661-4249.

More library news

The club wishes to pay a member, or a reliable person referred by a member, to complete the data input that will create an electronic card catalogue. This temporary, short-term position requires a typist with numeric keypad skills.

About 280 catalogue entries remain to be made. The Board has estimated the job at approximately 10 hours of typing, and is offering a rate of $7.50 per hour. The applicant must have access to a Windows-based PC (any version of Windows).

If you wish to apply, or recommend someone for this task, contact Chris Cody.

Moving our money

As announced last month, the reassignment of the club's fiscal assets is continuing. A new 90-day CD was opened in the amount of $2,500. It earns an APR of 4.69 percent.

This month, treasurer Gene Nassar will close the money market fund and use its proceeds to open a third CD. Our current financial standing is as follows.

Checking account $3,650.23
CD #1 $3,212.00
CD #2 $2,500.00
Money market $1,216.00
(plus interest from September 1 to the date of closing)

Once the money market account is closed and the final CD is opened, we will publish a precise statement.

Seven new members

During October, TVS grew to at least 210 total members. (Family memberships are counted as two, but actually include all members of the household.) New to us last month were: Greg Le Sage, Richard and Rae Duffus, Winston and Carole Bumpus, the James Brown Family, Jeff Curtis, Brian Knittel, and Tom Russell.

Members who join in October, November, or December receive a 1998 membership and the balance of 1997 for the regular membership price. If you know of someone who has delayed joining to avoid paying "double dues", please share this good news with him or her.

Your Yosemite donations at work

Club president Dave Anderson recently attended a special star party for individuals and representatives of groups who donated to the Yosemite Fund drive. The improvements at Glacier Point will make future star parties much more enjoyable.

A well-designed amphitheater is suitable for public presentations on astronomy. Space has been allocated so that groups can set up clusters of telescopes together. Electrical outlets are conveniently situated nearby. Red lights now illuminate the stone steps leading down to the lowest level. Concession buildings and rest rooms are completely upgraded, as are the new plantings, new trails, and much more accessible parking.

The latest in websites

Bay Area Astro. Classifieds,
Plasma rivers in the Sun, http:/
Suggested by Mike Rushford,

What's up for November

by Dave Anderson November 1 Sat Callisto occulted by Jupiter 9:21 PM Io transits 9:50 PM PST.
Algol at minimum 2:33 AM Eclipsing binary drops from mag. 2.1 to 3.4 in about 5 hours. (Period is 2.867 315 days). Compare Alpha Persei (mag. 1.79), Gamma Andromedae (2.2 6) and Delta Persei (3.01 ). 2 Sun Io occulted by Jupiter 6:59 PM, reappears from eclipse 10:36 PM
3 Mon Mars 6° and Venus 9° south of Moon.
Ganymede's shadow transits Jupiter until 6:35 PM Io transits until 6:36; shadow transits until 7: 55 PM
Ganymede's shadow eclipses Io (partial, 96% light drop) 10:23 to 10:55 PM Algol at minimum 11:22 PM 4 Tue Election Day.
Europa occulted by Jupiter 6:32 PM Delta Cephei at maximum 10:02 PM Variable rises to mag. 3.5 from 4.4 in about 1.5 days. (Period is 5.366 341 days). Compare Zeta Cephei (mag. 3.35) and Epsilon Cephei (mag. 4.2). 5 Wed Venus at greatest eastern elongation (47 ° ), but also at extreme southern declination (-27° 01'), making this a poor evening apparition for northern latitudes. 6 Thu Algol at minimum 8:11 PM
Galileo flyby of Europa (1,1 19 km). Europa's shadow transits Jupiter until 6:21 PM 7 Fri First Quarter Moon 1:43 PM
9 Sun Io occulted by Jupiter 8:54 PM
10 Mon Triple shadow transit and mutual satellite event on Jupiter: Callisto's shadow transits Jupiter 6:1 0 to
10:52 PM Io transits 6:15 to 8:32 PM; shadow transits 7:34 to 9:51 PM Ganymede's shadow transits 6:59 to 10:36 PM Ganymede's shadow eclipses Io (partial, 87% light drop) 8:24 to 8:43 p. m.
11 Tue Veterans' Day.
Saturn 0.4° south of Moon (occulted in Southeast U.S.). Io reappears from eclipse by Jupiter 7:01 PM Europa occulted 9:11 PM 13 Thu Europa transits Jupiter until 6:22 PM; shadow transits 6:08 to 8:58 PM
14 Fri Full Moon 6:12 AM
15 Sat Aldebaran 0.5° south of Moon (occulted in Middle East).
16 Sun Asteroid 9 Metis (mag 8.3) at opposition.
17 Mon Leonid meteor shower peaks about 3 AM (Build ing toward 1998 or 1999 meteor storm?)
Ganymede transits Jupiter 5:43 to 9:20 PM Io transits 8:12 PM; shadow transits 9:30 PM 18 Tue Callisto reappears from ooccultation by Jupiter 8:41 PM Io reappears from eclipse 8:56 PM
20 Thu Europa transits Jupiter 6:11 to 9:01 PM; shadow transits 8:45 PM
21 Fri Tri-Valley Stargazers meeting 7:30 PM Unitarian Universalist Church of Livermore, 1893 N. Vasco R oad,
Livermore (3/4 mile north of I-580). Last Quarter Moon 3:58 PM Delta Cephei at maximum 12:24 AM 22 Sat Europa reappears from eclipse by Jupiter 6:43 PM
24 Mon TVS Planning Meeting 7:00 PM Round Table Pizza, 1540 First St., Livermore
(in Orchard Supply/Longs/Safeway shopping center). Algol at minimum 1:04 AM 25 Tue Io occulted by Jupiter 7:18 PM
26 Wed Io transits Jupiter until 6:57 PM; shadow transits 5:55 to 8:11 PM
Algol at minimum 9:53 PM 27 Thu Thanksgiving Day.
Europa transits Jupiter 8:52 PM 28 Fri Mercury at greatest eastern elongation (22 ° ) in evening sky.
Ganymede reappears from eclipse by Jupiter 8:32 PM 29 Sat New Moon 6:14 PM Excellent weekend for observing.

December 1 Mon Mercury 7° south of Moon.
Io transits Jupiter 6:39 to 8:56 PM; shadow transits 7:50 PM PST. 2 Tue Mars 5° south of Moon.
3 Wed Venus 7° south of Moon. (Neptune and Uranus nearby).
4 Thu Jupiter 3° south of Moon.
Io reappears from eclipse by Jupiter 7:16 PM Space Shutt le Endeavor (STS-88) launch scheduled. (First International Space Station assembly mission.) 5 Fri Ganymede reappears from occultation by Jupiter 7:45 PM, eclipsed 8:54 PM
6 Sat First Quarter Moon 10:09 PM
Europa occulted by Jupiter 6:42 PM

Some Fall and Winter Deep-Sky Objects

M31, M32, M110 The Andromeda Galaxy and two companions. Huge and bright. Easi ly appreciated in binoculars or
unaided eye under reasonable skies. M33 Large, bright (mag. 5.7), but quite diffuse galaxy in Tri angulum.
NGC7331 Edge-on spiral galaxy in Pegasus.
NGC253 Large, bright galaxy in Sculptor.
NGC891 Faint, classic edge-on galaxy with dust-lanes in Andromeda.
NGC869 & 884 The Double Cluster in Perseus. Great in binoculars or telescope.
M1 The Crab Nebula, the remnant of the supernova of 1054 A.D.
NGC7789 A faint but very rich open cluster in Cassiopeia.
NGC7662 Blue Snowball planetary nebula in Andromeda.
M45 The Pleiades in Taurus. Best in binoculars.

Comet Commets

by Don Machholz


C/1995 O1 (Hale-Bopp) Date (00UT) R.A. (2000) Dec El Sky Mag
11-03 08h04.9m -51° 07' 83° M 6.7
11-08 08h01.2m -53° 00' 84° M 6.8
11-13 07h56.4m -54° 48' 86° M 6.9
11-18 07h50.5m -56° 29' 87° M 7.0
11-23 07h43.4m -58° 04' 89° M 7.1
11-28 07h35.0m -59° 30' 90° M 7.2
12-03 07h25.5m -60° 46' 91° M 7.3

C/1997 J2 (Meunier-Dupouy) Date (00UT) R.A. (2000) Dec El Sky Mag
11-03 16h42.0m +54° 25' 75° E 10.8
11-08 16h57.2m +53° 17' 75° E 10.8
11-13 17h12.3m +52° 08' 75° E 10.8
11-18 17h27.0m +50° 57' 74° E 10.7
11-23 17h41.5m +49° 45' 74° E 10.7
11-28 17h55.6m +48° 33' 73° E 10.7
12-03 18h09.4m +47° 21' 73° E 10.7

103P/ Hartley 2 Date (00UT) R.A. (2000) Dec El Sky Mag
11-03 19h42.5m -08° 04' 76° E 10.4
11-08 19h55.5m -08° 29' 74° E 10.1
11-13 20h09.7m -08° 51' 72° E 9.8
11-18 20h25.0m -09° 08' 71° E 9.5
11-23 20h41.5m -09° 20' 70° E 9.3
11-28 20h59.2m -09° 27' 69° E 9.1
12-03 21h18.1m -09° 29' 68° E 8.9

C/1997 T1 (Utsunomiya) Date (00UT) R.A. (2000) Dec El Sky Mag
11-03 19h01.2m +34° 24' 81° E 9.9
11-08 18h55.5m +29° 19' 74° E 10.0
11-13 18h51.7m +25° 00' 68° E 10.1
11-18 18h49.2m +21° 19' 63° E 10.2
11-23 18h47.7m +18° 09' 57° E 10.3
11-28 18h46.7m +15° 26' 52° E 10.3
12-03 18h46.3m +13° 05' 47° E 10.4

A new comet has been visually discovered. It can be seen in most telescopes for the next few months. Meanwhile, Comet Hale-Bopp dims as it moves south in the morning sky. Comet Meunier-Dupouy, up to a magnitude fainter than suggested in the ephemeris below, remains in our northern evening sky. Periodic Comet Hartley 2 has returned on its 6.4-year orbit. Finally, our monthly report on daylight comet discoveries shows five more short-lived faint comets being found on images obtained by the SOHO satellite, bringing its total to 30. The newly-discovered comet is C/1997 T1 (Utsunomiya). It was found on Oct. 4 by Syogo Utsunomiya of Japan who was using 6" binoculars at 25 power. The comet was quite far north (+72 degrees declination) and showed a short tail. An early orbit indicates that the comet reaches perihelion in early December when it will be outside our orbit and a bit behind us.

A second and much fainter comet was discovered on Oct. 5 by a team of professional observers using a CCD attached to a telescope at the European Southern Observatory. Found at magnitude 19, it appeared as an asteroid: a single slow-moving point of light. Closer examination has showed a tiny tail. It is possibly a short-period comet staying at least three astronomical units from the sun. It is known as P/1997 T3 and will remain faint.

Since the first day of 1975, 76 comets have been visually discovered. Some have been discovered by more than one person: ten by two visual discoverers and seven by three. This amounts to 100 visual discovery events. Thirty-two of those 76 comets were found in the evening sky with 44 found in the morning sky. Additionally, 42 were found in the north of the celestial equat or with 34 found south. All of the 23 comets found by observers living south of the equat or were found in the southern celestial sky. Northern Hemisphere observers found comets both north and south of the equator.

Orbital Elements

Object : Hale-Bopp Meunier-Dupouy
Peri. Date: 1997 04 01.1 3800 1998 03 10.4 346
Peri. Dist (AU): 0.914 1405 AU 3.050 393 AU
Arg/Peri (2000): 130.5 8915 deg. 122.6 927 deg.
Asc. Node (2000): 282.4 7069 deg. 148.8 384 deg.
Incl (2000): 089.4 2943 deg. 091.2 715 deg.
Eccen: 0.995 1172 1.001 491
Orbital Period: ~2500 years Long Period
Ref: MPC 2956 8 MPC 3042 9
Epoch: 1997 06 01 1998 03 08
Absol. Mag/"n": -1.0/4.0 3.0/4.0

Color Astrophotography: Which Film?

by Kenneth R. Sperber I've been doing prime focus astrophotography for the past two to three years, and I have enjoyed encouraging, if not more than reasonable success. One of the great benefits of being a TVS member is access to the fairly dark skies at the Sky Shack, and the opportunity this affords for observational and astrophotographic astronomy.
More importantly, TVS is home to many excellent astrophotographers from whom I've gleaned many helpful suggestions (thanks Jack, Chuck, Robert, Gene, Bob and Joe).

In the past couple of years, the market has seen the demise of the standard film for color astro photography, Fuji HG400. Fortunately, to the rescue come two exciting new color films, Kodak PPF and Kodak Ektapress Multispeed PJM. These new films have excellent reciprocity characteristics and very fine grain, and they have been the subject of recent reviews in Sky & Telescope (March 1997) and Astronomy (October 1996, May 1997).

All photos in this article were taken at the Sky Shack using my Meade LX200 10" f/10, equipped with a Lumicon Giant Easyguider that yields an effective focal ratio of approximately f/6.3. This reduced focal ratio has the advantage of requiring much reduced exposure times, as the exposure duration is proportional to the square of the focal ratio. Additionally, one is able to photograph a larger field of view due to the reduced image scale. All photos have been manually guided.

To perform the intercomparison of various films, I have photographed M17, the Swan Nebula, for 30 minutes (with one exception) using a Lumicon Deep-Sky filter. I've chosen M17 due to the range of nebulosity this object displays. The best available prints were scanned in black and white mode, and then reversed to highlight the faint nebulosity. Unfortunately, I do not have access to a negative scanner or advanced image processings oftware which might allow for a more exacting intercomparison. However, the results discussed below are consistent with the degree of nebulosity recorded on the negatives.

The hypered film for Figures 1 and 6 was purchased from Lumicon. I hypered the film for Figures 3-5 at home using a Lumicon 300 hyper-kit. The PJM and PPF for Figures 3-4 were hypered together, each in its respective 35mm cartridges, for 12 hours at 50 degrees C, at a pressure of +3 psi. For Figure 5, the PPF was prepared in the same manner, but the hypering duration was only five hours. The images in Figures 3-5 were taken on the same night, and were processed and printed at the same lab at the same time, thus yielding a control led experiment that isolates the different characteristics of PPF and PJM, as well as the effect of different hypering times for PPF.

During my early efforts at astrophotography, I used the fastest available film, which at that time was hypered Konica SR-V3200, in order to keep exposure times as short as possible while I honed my guiding technique and polar alignment skills. As seen in Figure 1, the "swan" and some of the surrounding nebulosity are evident in this image. Although this exposure is of shorter duration than those presented in Figure 2-6 (hence the degree of nebulosity captured in this exposure relative to the others is not a fair comparison), this film has the undesirable quality of being very grainy.

The remaining photos were taken with either Kodak PJM or PPF under a variety of hypersensitizing scenerios, all using the same exposure time.

Figure 2 is a "control" photo taken with unhypered PJM to illustrate the benefits of hypering. Even unhypered, the impressive red response of this film is evident, as it captures the brightest portion of the nebula quite well. However, the faint nebulosity is barely recorded, and also note the dearth of stars relative to the other photos. Unhypered, this film suffers from a poor dynamic range as evidenced by the "flat" uniform tones of the brightest portions of the nebula.

The amazing benefit of hypering PJM (12 hours) is evident in Figure. 3. Rich and complex nebulosity that previously was not evident gives M17 a 3-dimensional-like quality.
As seen in Figure 4, the degree of nebulosity captured by hypered PPF (12 hours) is even more impressive, with emission apparent over the vast majority of the photo. Thus, in my experience, hypered PPF outperforms hypered PJM in its red sensitivity. This result conflicts with the experience of Jerry Lodriguss (see Astronomy , May 1997). However, I believe this discrepancy is due to the different hypersensitization times that Mr. Lodriguss and I have used for PPF (we both use 12 hours for PJM). According to his web page, Mr. Lodriguss uses a hypering time of five hours for PPF based on his sensitivity tests to yi eld a neutral density of 0.1 relative to unhypered PPF. I hypered PPF for 12 hours based on a recommendation from Jack Marling. To test my hy pothesis that the conflicting PPF/PJM red sensitivity is due to the different hypering times,
I show in Figure 5 an exposure with PPF that I had hypered for 5 hours. Clearly, PPF that is hypered for only 5 hours gives inferior results relative to PJM and PPF that are hypered for 12 hours. This indicates that PPF does indeed have a superior red response relative to PJM for the same hypering duration.

Figure 6 is an identical exposure taken on PPF that was hypered at Lumicon. The degree of nebulosity captured is not as good as that from the PPF I hypered at home for 12 hours. Rather, it is comparable to the PPF that I home-hypered for five hours. This, however, is not a controlled experiment for several reasons. 1) The Lumicon PPF for Figure 6 was not fresh; I had stored it in my freezer for about two months prior to exposure, 2) This photo was taken on a different night and sky conditions may not have been identical, 3) It was processed at a different time (but at the same lab as all other photos). The recommended storage time of hypered color film is only about one month, and I have been told that freshly hypered film can be about twice as fast as that which has been prepared commercially and shipped through the mail (Jack Marling, personal communication, 1997). Thus, the poorer red response seen in Figure 6 is probably due to reduced sensitivity as a result of the two-month storage time. The main result of Figure 6 is that even with the two-month storage time, PPF retains a fair degree of hypersensitization, resulting in a pleasing image. Additionally, Figure 6 suggests that hypered PPF is preferable to hypered Konica SR-V3200 (Figure 1). A 20-minute exposure on commercially hypered PPF would likely yield comparable nebulosity (if not better) than that captured by the SR-V3200. It is likely that hypered PPF is as fast as hypered R-V3200, but the finer grain of the PPF makes it the color film of choice for the beginning (as well as the experienced) astrophotographer, in my opinion. However, a controlled experiment is warranted before this hypothesis can be justified.

Both PPF and PJM are exciting new color films for astrophotography. My personal experience, in this limited sensitivity experiment of photographing emission nebula, suggests that PPF has a better red response than PJM. Whether, you purchase hypered film commercially, or you bake it yourself, these films will result in striking astrophotos, provided of course that you have good polar alignment and guiding technique. I have yet to compare the blue response of these films in a systematic fashion (the Pleiades are on the rise), and I encourage others to perform similar intercomparisons. The result will be rewarding not only to you, but to other astrophotographers, particularly those who are just starting out.

I would like to thank Dr. Jack Marling and Mr. Jerry Lodriguss for reviewing this article.

Stellar Seller

Editor's note: This column is an irregular feature, offered to assist TVS members in buy ing or selling used astronomica equipment and supplies. To submit items offered for sale or wanted for purchase, e-mail the newsletter editor at TVS provides this service, without warranties, expressed or implied. Purchasers should make all their own inquiries before buying any items offered in Stellar Seller.

The entire contents of amateur astronomer Quentin Fritzsche's home observatory are for sale. These include telescopes, filters, tripods, eyepieces, adaptors, books, VCRs, monitors, televisions, disk players, assorted video equipment, and electronic components. A comprehensive list of the items is available from Leonard Higgins of Napa. Leonard, himself an amateur astronomer, is assisting Gloria Fritzsche in the disposition of her late husband's stargazing equipment. You may reach Leonard in the evening at (707) 252-9110, or by e-mail, mountain@comm He will send a copy of the inventory and prices.


Carl Sagan "Cosmos" video tape set. Does anyone have an old set they would be willing to sell for not-too-much-money? If so, please contact Deborah Scherrer at (510) 881-4489 or deborah@quake. stanford. edu.

Stanford SOLAR Center - online

Want to explore the Sun, online? You are invited to visit Stanford's new educational Website, providing solar online activities and information about solar science exploration. The site is accessed at

The SOLAR Center is sponsored by the NASA-funded Solar Physics group at Stanford. It was produced by a team led by club member Deborah Scherrer. Images and data are provided by the SOHO spacecraft and, more particularly, by the MDI instrument from the Solar Oscillations Investigation team. Phil Scherrer, also a club member, is the SOI/MDI principal investigator.

The site offers a multi-disciplinary interactive approach to exploring the Sun. Activities range from simple visual quizzes to weeks-long observations and analyses. Although the site was designed with specific activities for students at grade levels 4 through 12, adults also find much that is intriguing at the site. Directions for making a pinhole camera or using an H-alpha filter are given in detail. A pointer to Mike Rushford's solar Eyes on the Skies solar telescope has been posted.

To capture the interest of kids in various ways, Deborah's team has inserted the following elements: solar art (particularly that developed as calibration or data visualization imagery) ; folklore about and multicultural interpretations of the Sun; solar literature (What do you think Hamlet has to do with astronomy?); solar rock art; ancient solar astronomy sites and models; and a "sun-on-earth" section discussing rainbows, sun pillars, the green flash, sun fish, and sunflowers.

You are invited to explore this site, and send your comments or suggestions. The pages will be enhanced continuously.

President Dave Anderson (510) 661-4249
Secretary Bill Burnap (510) 449-4552
Vice President Chuck Grant (510) 449-1500
Treasurer Gene Nassar (510) 462-7843
Observatory Director Chuck Grant (510) 449-1500
Librarian Chris Cody (707) 747-6550
Eyes on the Skies Mike Rushford
Web Site
Editor Alane Alchorn (510) 455-9464 (510) 455-9466 fax
Membership: 210
Meeting Location Unitarian Universalist Church in Livermore 1893 N. Vasco Rd. 3/4 mile north of I-580

Board Alane Alchorn Dennis Beckley Rich Combs Rich Green Russ Kirk Dave Rodrigues Debbie Scherrer Al Smith Dave Sworin Jim Zumstein

Tri-Valley Stargazers

P.O. Box 2467
Livermore, CA 94551

Tri-Valley Stargazers Membership/Renewal Application

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